Striped wings !!

Hi!! both the front wing of my rrd alu2 and the stabilizer have scratches due to touches at the bottom and small touches with stones! Obviously, if those small wings raise my 100Kg, some negative effect must have imperfections on both the lower and upper surface and not even speak on the leading edge! If someone has happened as it has solved? have they filled, sanded, varnished? Thanks for the answers!!!

I do sanding for small scratches, but use epoxy or some polyester based substance ("de ijssel" poltix or variopox, not sure, but its a dutch brand) for bigger dings. Which one i use depends on time, since the poly one is dry in 20 minutes and I'll be ready to sail in 30 after applying it often gets my preference, although the epoxy one is supposed to be better with carbon. I haven't really noticed any differences besides the drying times, I think because it has no structural function.

The difference is very noticable if you're going for speed / racing, if you're not then I wouldnt worry too much unless you have big (more than 2mm across/deep) dings in the leading edge. Big dings in the leading edge can have huge bad effects, makes the foil wobble / lose lift because of the imperfect profile. Leads to some strange sensation.

Sanding I start with 200 grit mostly, end with 800 or 1000 for the wings and 3000 for the mast. You want the mast as fine as you can, but the wings need some "imperfection" because that has been shown to improve flow by the water "sticking" to the wing.

White of Heart,
.....the wings need some "imperfection" because that has been shown to improve flow by the water "sticking" to the wing....

Do you think foils should be designed to have a rough surface like the leading edge of an aircraft wing, to encourage turbulent flow (and flow "stickiness")?

I have been using automotive glazing and spot putty. Dries quickly sands easily. I then spray some paint on it. It is great for the small marks and scratches. Not sure I feel any difference afterwards but the wing looks great again.

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foilarg said..
Thanks, for the answers, do I have 2 component epoxy or better car putty? after application and sanding some type of varnish? Is sanding in any special direction? thanks

How deep are the scratches? If just surface scratches, car putty, primer, clear coat - whatever matches your present finish is easiest. If it's matte black, use black. Clear, then use clear. Masking tape is your friend for not overspraying the entire wing and having to sand more than you need to.

If it's a deeper scratch, go to the harder stuff. If you do epoxy, consider mixing in some glass cells, etc and try not to pile it on, Use a plastic scraper like an old credit card or spreader so you have to do the least sanding possible. It's better to do a couple of coats than pile it on and spend a lot of time sanding. You'll be wanting to use pretty fine grit sanding paper so you don't scratch the good material beside the scratches and have to sand that too much or you'll start reshaping the wing.

Oh, and I try to hop off before I get to the shallows and swim it in until I touch bottom and then flip the board over. But we all misjudge that sometimes.

Yes!! it's true I sail on the Rio de la Plata, sometimes high tide sometimes low tide !! some areas of stones and dark waters !!! and calculation errors .... and many days sailing with the foil this last year !! 10 times more than traditional windsurfing! and 10 times more wear!